Re: [PATCH v11 6/9] ACPI: x86: s2idle: Add a function to get constraints for a device

From: Andy Shevchenko
Date: Thu Aug 10 2023 - 11:47:53 EST


On Wed, Aug 09, 2023 at 01:54:50PM -0500, Mario Limonciello wrote:
> Other parts of the kernel may use constraints information to make
> decisions on what power state to put a device into.

...

> +int acpi_get_lps0_constraint(struct device *dev)
> +{

> + int i;
> +
> + for (i = 0; i < lpi_constraints_table_size; ++i) {
> + static struct lpi_constraints *entry;

static?!

Seems to me with the code in lpi_check_constraints() this actually can be first
(separate patch maybe with conversion of the mentioned user) transformed to

#define for_each_lpi_constraint(entry)
for (int i = 0;
entry = &lpi_constraints_table[i], i < lpi_constraints_table_size;
i++)

> + int val;
> +
> + entry = &lpi_constraints_table[i];
> + if (!device_match_acpi_handle(dev, entry->handle))
> + continue;
> + val = entry->enabled ? entry->min_dstate : 0;
> + acpi_handle_debug(entry->handle,
> + "ACPI device constraint: %d\n", val);
> + return val;
> + }

So will become

struct lpi_constraints *entry;
int val;

for_each_lpi_constraint(entry) {
if (!device_match_acpi_handle(dev, entry->handle))
continue;
val = entry->enabled ? entry->min_dstate : 0;
acpi_handle_debug(entry->handle,
"ACPI device constraint: %d\n", val);
return val;
}

> + return -ENODEV;
> +}

--
With Best Regards,
Andy Shevchenko